While it was originally believed that retrosaurs went extinct at the end of the Mesozoic era, in truth many survived. The vast majority of these prehistoric relics withstood extinction by becoming kaiju, living deep within the Yamaneon tunnel system beneath the surface of the earth. However, these enormous beasts were not the sole survivors of the clade. Other retrosaurs survived thanks to the efforts of the most intelligent species in the clade: the reptodites.
Members of the carnivorous Paleo Tyrant clade (and specifically of the Tiny Tyrant subclade), Reptodites are obligate carnivores. Their perilously high position on the food chain has informed their worldview, as reptodite populations that don’t manage and cultivate their environment, and more specifically the multitude of less powerful creatures they depend upon in that environment, don’t last very long. Early reptodite civilization focused on a nomadic lifestyle of animal herding, and slowly grew into a culture that focused on ecosystem protection and stability.
The average Reptodite stands between 7 and 8 feet tall, though specimens as tall as 10 feet or as short as 6 feet are not unheard of. They come in a variety of color morphs: while most Reptodites are green or brown, blue, red, orange, and even yellow Reptodites are not unheard of. Though they are adapted for a nocturnal lifestyle, Reptodites are active at both day and night time, and likewise split up their sleep between both periods of the day.
Reptodites are sapient and civilized creatures, with a languages, cultures, tools, and customs all their own. In some ways their culture is vastly more “primitive” than humanity’s – reptodite tools of war are rarely more advanced than bronze age weapons, for example. Yet in other respects they are unfathomably advanced – they have an incredibly knowledge of bioengineering and animal husbandry, as ecology has been a major focus of their civilization since before they went underground.
Currently, all Reptodite colonies exist in underground tunnels parallel to the Yamaneon tunnel system. These tunnels are lit by Yamaneon crystals that are contained in radiation shielded casings, allowing the Reptodites to siphon the Yamaneon light and energy without succumbing to the mutating effects of its radiation. With this crucial technology, Reptodites have managed to make underground recreations of their old Mesozoic environments, which is one of many reasons they have elected not to retake the surface world – their underground habitats suit them much better.
The old Reptodites did not leave their animal companions behind when they retreated underground, and modern Reptodite societies still employ a vast array of trained animal helpers in addition to livestock. Such helpers include but are not limited to:
Shepherd beasts: perhaps the most important and crucial members of the Reptodites many domesticated species, these massive Paleo Tyrants stand 20 feet tall and 50 feet long. They are relatives of Manospondylus gigas and Dynamosaurus imperiosus, some of the last and largest members of the Paleo Tyrant clade. Shepherd beasts help wrangle and guide other Reptodite beasts of burden, as their presence immediately intimidates almost every other species. They are incredibly intelligent and strong willed, requiring years of training from the day they hatch before they can be used in the field.
Construction beasts: members of various herbivorous clades of retrosaur are used by the Reptodites to ready the earth for new buildings and other necessary constructs. While Reptodite shelters are fairly small compared to human buildings (they have nothing as large as a skyscraper), they still require a great deal of prep work before they can be set up.
Pets: two strange species of lizards have been domesticated by Reptodites for seemingly little purpose save for amusement and companionship. The first species, with its long neck and blunt snout, is particularly friendly and outgoing, while the second, fang-bearing species can be rather aloof and skittish around strangers.
While human civilization spent thousands of years ignorant of the existence of their subterranean predecessors, Reptodites have known about us for quite some time. More importantly, they are also aware of life on other planets. The Mesozoic Reptodites were saved by intervention and aid from the sapient Martians, and have been in constant communication with their planetary neighbors ever since. The Martians also made them aware of the threat posed by the Beyonder Alliance, and while humans built their shining cities and waged war upon each other, the Reptodites slowly but surely prepared for an invasion by a force the likes of which humanity could scarcely fathom.